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Chemical Structural Features Of Pyridine Extracts Of The Argonne Premium Coals Using 13c Nmr Spectroscopy, Thomas H. Fletcher, S Bai, Ronald J. Pugmire, Steven Wood, David M. Grant Jan 1993

Chemical Structural Features Of Pyridine Extracts Of The Argonne Premium Coals Using 13c Nmr Spectroscopy, Thomas H. Fletcher, S Bai, Ronald J. Pugmire, Steven Wood, David M. Grant

Faculty Publications

Soxhlet extractions were performed on the eight Argonne Premium coals using pyridine purged with argon and followed by a novel washing procedure to remove the pyridine. Mass closure (extracts plus residues) on duplicate experiments accounted for 94-96% of the original coal, repeatable to within 2%. Chemical structural features determined from 13C NMR analyses of the extracts and residues showed more attachments per aromatic cluster for the residues, indicating a greater degree of covalent bonding in the residue than in the extract. 1H NMR analysis of the extracts showed a gradual increase in the hydrogen aromaticity with rank, along …

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Design Of A Functional Calcium Channel Protein: Inferences About An Ion Channel‐Forming Motif Derived From The Primary Structure Of Voltage‐Gated Calcium Channels, Anne Grove, John M. Tomich, Takeo Iwamoto, Mauricio Montal Jan 1993

Design Of A Functional Calcium Channel Protein: Inferences About An Ion Channel‐Forming Motif Derived From The Primary Structure Of Voltage‐Gated Calcium Channels, Anne Grove, John M. Tomich, Takeo Iwamoto, Mauricio Montal

Faculty Publications

To identify sequence‐specific motifs associated with the formation of an ionic pore, we systematically evaluated the channel‐forming activity of synthetic peptides with sequence of predicted transmembrane segments of the voltage‐gated calcium channel. The amino acid sequence of voltage‐gated, dihydropyridine (DHP)‐sensitive calcium channels suggests the presence in each of four homologous repeats (I–IV) of six segments (S1–S6) predicted to form membrane‐spanning, α‐helical structures. Only peptides representing amphipathic segments S2 or S3 form channels in lipid bilayers. To generate a functional calcium channel based on a four‐helix bundle motif, four‐helix bundle proteins representing IVS2 (T4CaIVS2) or IVS3 (T4CaIVS3) were synthesized. Both proteins …

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Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King Jan 1993

Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King

Faculty Publications

Rates of methane consumption were measured in subarctic coniferous and temperate mixed-hardwood forest soils, using static chambers and intact soil cores. Rates at both sites were generally between 1 and 3 mg of CH4 m-2 day-1 and decreased with increasing soil water contents above 20%. Addition of ammonium (1 μmol g of soil-1) strongly inhibited methane oxidation in the subarctic soils; a lesser inhibition was observed for temperate forest samples. The response to nitrogen additions occurred within a few hours and was probably due to physiological changes in the active methane-consuming populations. Methane consumption in soils from both sites was …

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Solid-State Deuterium Nmr Spectroscopy Of D5-Phenol In White Portland Cement: A New Method For Assessing Solidification/Stabilization, Michael A. Janusa, Xiao Wu, Frank K. Cartledge, Leslie G. Butler Jan 1993

Solid-State Deuterium Nmr Spectroscopy Of D5-Phenol In White Portland Cement: A New Method For Assessing Solidification/Stabilization, Michael A. Janusa, Xiao Wu, Frank K. Cartledge, Leslie G. Butler

Faculty Publications

We have developed a new NMR-based procedure for studying waste/cement interactions. This is the first use of deuterium NMR spectroscopy to study waste solidification/stabilization (S/S). The main feature of deuterium NMR spectroscopy is the ability to monitor molecular reorientations over a wide range of reorientation rates. This technique allows one to determine if a particular deuterated organic waste is effectively solidified/stabilized and to determine the lower limit of the bond strength between the waste and the cement matrix. Comparison of the predicted and experimental deuterium NMR spectra show that phenol is mainly dissolved in pore waters and, thus, poorly immobilized …

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Cyberspace, The Free Market And The Free Marketplace Of Ideas: Recognizing Legal Differences In Computer Bulletin Board Functions, Eric Goldman Jan 1993

Cyberspace, The Free Market And The Free Marketplace Of Ideas: Recognizing Legal Differences In Computer Bulletin Board Functions, Eric Goldman

Faculty Publications

No abstract provided.

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Results From The Soviet-American Gallium Experiment, O. L. Anosov, E. L. Faizov, V. N. Gavrin, A. V. Kalikhov, T. V. Knodel, I. I. Knyshenko, V. N. Kornoukhov, I. N. Mirmov, A. V. Ostrinsky, A. M. Pshukov, A. A. Shikhin, P. V. Timofeyev, E. P. Veretenkin, V. M. Vermul, G. T. Zatsepin, T. J. Bowles, S. R. Elliott, J. S. Nico, H. A. O'Brien, D. L. Wark, J. F. Wilkerson, B. T. Cleveland, R. Davis, K. Lande, M. L. Cherry, R. T. Kouzes Jan 1993

Results From The Soviet-American Gallium Experiment, O. L. Anosov, E. L. Faizov, V. N. Gavrin, A. V. Kalikhov, T. V. Knodel, I. I. Knyshenko, V. N. Kornoukhov, I. N. Mirmov, A. V. Ostrinsky, A. M. Pshukov, A. A. Shikhin, P. V. Timofeyev, E. P. Veretenkin, V. M. Vermul, G. T. Zatsepin, T. J. Bowles, S. R. Elliott, J. S. Nico, H. A. O'Brien, D. L. Wark, J. F. Wilkerson, B. T. Cleveland, R. Davis, K. Lande, M. L. Cherry, R. T. Kouzes

Faculty Publications

A radiochemical 71Ga-71Ge experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of 71Ge atoms extracted from 30 tons of gallium in 1990 and 57 tons in 1991 was measured in twelve runs during the period of January 1990 to December 1991. For the 1990 data, we observed the capture rate to be 20 + 15 -20 (stat) ± 32 (syst) SNU, resulting in a limit of less than 79 SNU (90% CL). This is to be compared with 132 SNU predicted …

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Difficulties And Characteristics Of Students From Developing Countries In Using American Libraries, Ziming Liu Jan 1993

Difficulties And Characteristics Of Students From Developing Countries In Using American Libraries, Ziming Liu

Faculty Publications

No abstract provided.

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An Overview Of Acerc Research In Fuel Characterization And Reaction Mechanisms, Ronald J. Pugmire, Thomas H. Fletcher Jan 1993

An Overview Of Acerc Research In Fuel Characterization And Reaction Mechanisms, Ronald J. Pugmire, Thomas H. Fletcher

Faculty Publications

A major objective of the Advanced Combustion Engineering Research Center is the development and verification of data on fuel characterization and reaction mechanisms and rates that can be incorporated into submodels for use in the comprehensive combustion codes. As technology has advanced, the levels of analytical sophistication has also advanced, making it possible to augment the existing body of information with new data. From this new data it is possible to draw new insights regarding the complex nature of coal and the various processes associated with combustion. The ACERC program has made it possible to bring different disciplines together to …

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Private Practice For Public Consumption: Two Views Of Corporate Law, Jayne W. Barnard Jan 1993

Private Practice For Public Consumption: Two Views Of Corporate Law, Jayne W. Barnard

Faculty Publications

No abstract provided.

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Fighting Hate Violence By Taking Perpetrators To Court, Angelo N. Ancheta Jan 1993

Fighting Hate Violence By Taking Perpetrators To Court, Angelo N. Ancheta

Faculty Publications

No abstract provided.

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Community Lawyering [Review Essay], Angelo N. Ancheta Jan 1993

Community Lawyering [Review Essay], Angelo N. Ancheta

Faculty Publications

No abstract provided.

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Private Networks, Public Speech: Constitutional Speech Dimensions Of Access To Private Networks, Allen S. Hammond Iv Jan 1993

Private Networks, Public Speech: Constitutional Speech Dimensions Of Access To Private Networks, Allen S. Hammond Iv

Faculty Publications

No abstract provided.

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Ten Paradoxes Of Environmental Law, Kenneth A. Manaster Jan 1993

Ten Paradoxes Of Environmental Law, Kenneth A. Manaster

Faculty Publications

No abstract provided.

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The Moral Foundations Of Products Liability Law: Toward First Principles, David G. Owen Jan 1993

The Moral Foundations Of Products Liability Law: Toward First Principles, David G. Owen

Faculty Publications

No abstract provided.

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Mathematical Modeling Of The Formation Of Calcareous Deposits On Cathodically Protected Steel In Seawater, J. F. Yan, T. V. Nguyen, Ralph E. White, R. B. Griffin Jan 1993

Mathematical Modeling Of The Formation Of Calcareous Deposits On Cathodically Protected Steel In Seawater, J. F. Yan, T. V. Nguyen, Ralph E. White, R. B. Griffin

Faculty Publications

A first principle mathematical model of the formation of calcareous deposits on a cathodically protected steel rotatingdisk electrode in seawater is presented. The model includes equations which transport phenomena, electrochemical reactions,precipitation reactions, and a homogeneous reaction involved in the formation of calcareous deposits on an electrodesurface. Predicted concentration profiles show that a high concentration of OH– ions on the electrode surface leads to the formation of calcareous deposits. The calcareous deposits contain mostly CaCO3, but the initial deposits are predicted to contain more Mg(OH)2 than CaCO3. The predicted calcareous deposits on the electrode surface …

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Parametric Studies Of The Formation Of Calcareous Deposits On Cathodically Protected Steel In Seawater, J. F. Yan, Ralph E. White, R. B. Griffin Jan 1993

Parametric Studies Of The Formation Of Calcareous Deposits On Cathodically Protected Steel In Seawater, J. F. Yan, Ralph E. White, R. B. Griffin

Faculty Publications

A first principle mathematical model has been used to study the effects of ocean environment and cathodic protection on the formation of calcareous deposits and their ability to reduce the cathodic current density. These parameters include applied potential, rotation speed, temperature, salinity, and depth. The results showed the applied potential strongly influences the formation of calcareous deposits and their ability to reduce the cathodic current density. Among the environmental factors, rotation speed has the most influence on the cathodic current density. Salinity slightly influences the cathodic current density over the range of interest. Temperature is much more influential than salinity …

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A Water And Heat Management Model For Proton-Exchange-Membrane Fuel Cells, Trung V. Nguyen, Ralph E. White Jan 1993

A Water And Heat Management Model For Proton-Exchange-Membrane Fuel Cells, Trung V. Nguyen, Ralph E. White

Faculty Publications

Proper water and heat management are essential for obtaining high-power-density performance at high energy efficiency for proton-exchange-membrane fuel cells. A water and heat management model was developed and used to investigate the effectiveness of various humidification designs. The model accounts for water transport across the membrane by electro-osmosis and diffusion, heat transfer from the solid phase to the gas phase and latent heat associated with water evaporation and condensation in the flow channels. Results from the model showed that at high current densities (> 1 A/cm2) ohmic loss in the membrane accounts for a large fraction of the …

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Relationship Between Vegetation And Soil Formation In A Rapidly Submerging Coastal Marsh, J. A. Nyman, R. D. Delaune, H. H. Roberts, W. H. Patrick Jan 1993

Relationship Between Vegetation And Soil Formation In A Rapidly Submerging Coastal Marsh, J. A. Nyman, R. D. Delaune, H. H. Roberts, W. H. Patrick

Faculty Publications

In a Terrebonne Basin (Louisiana) marsh, Cs dating indicated that vertical accretion (0.98cm yr ) was extremely rapid relative to other marshes, but insufficient to counter submergence (1.38cm yr ). Mineral and organic matter accumulation were similar to that in other marshes. This marsh is threatened by a positive feedback loop of plant flooding stress and inadequate vertical accretion. Inadequate plant growth limits vertical accretion, which further increases flooding and decreases plant production. Thus plant production partly determines the degree of submergence some coastal and estuarine marshes will tolerate. -from Authors 137 -1 -1

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Projection Solutions Of Frobenius-Perron Operator Equations, Jiu Ding, Tien Tien Li Jan 1993

Projection Solutions Of Frobenius-Perron Operator Equations, Jiu Ding, Tien Tien Li

Faculty Publications

We construct in this paper the first order and second order piecewise polynomial finite approximation schemes for the computation of invariant measures of a class of nonsingular measurable transformations on the unit interval of the real axis. These schemes are based on the Galerkin’s projection method for L1-spaces and are proved to be convergent for the class of Frobenius-Perron operators.

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What's New In Intellectual Property - Business Is Booming In Copyright, Trademark And Patent Law, Richard C. Reuben Jan 1993

What's New In Intellectual Property - Business Is Booming In Copyright, Trademark And Patent Law, Richard C. Reuben

Faculty Publications

Forget the trendy law practice areas of the 1980s, such as mergers and acquisitions, real estate and antitrust. Intellectual property is where the action will be in the 1990s.

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Surface Treatment For Mitigation Of Hydrogen Absorption And Penetration Into Aisi 4340 Steel, G. Zheng, Branko N. Popov, Ralph E. White Jan 1993

Surface Treatment For Mitigation Of Hydrogen Absorption And Penetration Into Aisi 4340 Steel, G. Zheng, Branko N. Popov, Ralph E. White

Faculty Publications

The effectiveness of underpotential deposition of Pb onto a membrane made of AISI 4340 steel on the reduction of the hydrogen evolution reaction on the membrane and the degree of hydrogen ingress into the membrane was determined. In the presence of a monolayer coverage of Pb on the membrane surface, the hydrogen evolution currents were reduced by a factor of two compared with the values obtained on bare steel, and the steady-state hydrogen permeation flux through the steel membranes was reduced by 71%.

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Impedance Spectroscopy As A Nondestructive Health Interrogation Tool For Lithium-Bcx Cells, Branko N. Popov, W. Zhang, E. C. Darcy, Ralph E. White Jan 1993

Impedance Spectroscopy As A Nondestructive Health Interrogation Tool For Lithium-Bcx Cells, Branko N. Popov, W. Zhang, E. C. Darcy, Ralph E. White

Faculty Publications

The objective of this investigation was to study the growth of thick passivating layers on the Li anode in Li/BCX(Li/SOCl2 + BrCl) cells which were stored for a period of 3 years. Impedance spectroscopy and equivalent circuit models were used to determine characterizing parameters for these cells. The equivalent circuit used for virgin cells includes a faradic contribution and diffusion of the electroactive species. The equivalent circuit for batteries stored 1 or 2 years includes the impedance of a metal/passive film interface, the resistance of the film, and the impedance of the passivating film/electrolyte interface. The equivalent circuit used …

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Using Electrochemical Impedance Spectroscopy As A Tool For Organic Coating Solute Saturation Monitoring, Branko N. Popov, Mohammed A. Alwohaibi, Ralph E. White Jan 1993

Using Electrochemical Impedance Spectroscopy As A Tool For Organic Coating Solute Saturation Monitoring, Branko N. Popov, Mohammed A. Alwohaibi, Ralph E. White

Faculty Publications

Electrochemical impedance spectroscopy (EIS) has been used to study the solute uptake for epoxy/phenolic (E/p) andepoxy/amine (E/a) thick-coated mild steel samples immersed for 160 days in 3.5 weight percent NaCl solution exposed to air. Samples with thicknesses of approximately 200 µm with an exposed surface area of 22.6 cm2 were used to follow solute saturation of the organic coating. Good agreement was obtained between the calculated and measured coating capacitance when, according to the diffusion equation, the coating capacitance was plotted against exposure time.

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Galvanostatic Pulse And Pulse Reverse Plating Of Nickel-Iron Alloys From Electrolytes Containing Organic Compounds On A Rotating Disk Electrode, Branko N. Popov, Ken-Ming Yin, Ralph E. White Jan 1993

Galvanostatic Pulse And Pulse Reverse Plating Of Nickel-Iron Alloys From Electrolytes Containing Organic Compounds On A Rotating Disk Electrode, Branko N. Popov, Ken-Ming Yin, Ralph E. White

Faculty Publications

Linear sweep voltammetry, galvanostatic pulse, and pulse reverse techniques were used to study the plating of nickel-iron alloys in the presence of organic additives. The effects of pulse current densities, ip, reverse current densities, ir, rotation speed of disk electrode, and the presence of organic additives on deposition of nickel-iron alloys are evaluated. The observed phenomena can be explained by the concentration depletion of reactants (or products), and the surface coverage of the additives on the electrode. A new formulation of the plating bath is defined.

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Impedance Analysis For Oxygen Reduction In A Lithium Carbonate Melt: Effects Of Partial Pressure Of Carbon Dioxide And Temperature, Bhasker B. Dave, Ralph E. White, Supramaniam Srinivasan, A. John Appleby Jan 1993

Impedance Analysis For Oxygen Reduction In A Lithium Carbonate Melt: Effects Of Partial Pressure Of Carbon Dioxide And Temperature, Bhasker B. Dave, Ralph E. White, Supramaniam Srinivasan, A. John Appleby

Faculty Publications

Effects of partial pressure of carbon dioxide and temperature on oxygen reduction kinetics on a gold electrode in a lithium carbonate melt were examined using electrochemical impedance spectroscopic (EIS) and linear sweep voltammetric techniques. The impedance spectra were analyzed by a complex nonlinear least squares method, using the Randles-Ershler equivalent circuit model, to determine the electrode-kinetic and the mass-transfer parameters such as the charge-transfer resistance and the Warburg coefficient. The cyclic voltammetric measurements indicated that the oxygen reduction process in lithium carbonate melt is "reversible" up to 200 mV/s. The product DC0 determined by cyclic voltammetry agreed well …

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Thermal Analysis Of Spirally Wound Li/Bcx And Li/Socl2 Cells, E. E. Kalu, Ralph E. White Jan 1993

Thermal Analysis Of Spirally Wound Li/Bcx And Li/Socl2 Cells, E. E. Kalu, Ralph E. White

Faculty Publications

A thermal analysis of Li/BCX and high rate Li/SOCl2 cells is presented. The thermal model developed was used to study the effect of ambient temperature of discharge (0–40°C) on Li/BCX cells discharged at the same rate. The model predictions show that ambient temperature of discharge was critical in thermal management of the cell. For forced convection cooled cells, the model predicted that ambient temperature near room temperature (25°C) was required to achieve the lowest maximum temperature rise in the cell. Inclusion of the effects of reaction products to the model predictions showed that a constant composition assumption may be …

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Progress In Coal Pyrolysis, Peter R. Solomon, Thomas H. Fletcher, Ronald J. Pugmire Jan 1993

Progress In Coal Pyrolysis, Peter R. Solomon, Thomas H. Fletcher, Ronald J. Pugmire

Faculty Publications

The heterogeneous nature of coal and the complexity of the pyrolysis process have made it very difficult to perform unambiguous experiments to determine the rates and mechanisms in coal pyrolysis. However, recent years have seen a number of new experimental and theoretical approaches which shed new light on the subject. This paper considers the recent progress on kinetics, the formation of volatile products, network models, cross-linking, rank effects, and the ‘two-component’ model of coal structure. Recent experiments which measured coal particle temperatures at high heating rates provide reasonable agreement on kinetic rate constants. These rates also agree with those derived …

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Aerodynamic And Acoustic Changes Following Intensive Voice Therapy For Patients With Parkinson's Disease: A Case Study, Christopher Dromey, Lorraine O. Ramig, Ronald Scherer Jan 1993

Aerodynamic And Acoustic Changes Following Intensive Voice Therapy For Patients With Parkinson's Disease: A Case Study, Christopher Dromey, Lorraine O. Ramig, Ronald Scherer

Faculty Publications

No abstract provided.

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Swelling Properties Of Coal Chars During Rapid Coal Pyrolysis And Combustion,, Thomas H. Fletcher Jan 1993

Swelling Properties Of Coal Chars During Rapid Coal Pyrolysis And Combustion,, Thomas H. Fletcher

Faculty Publications

Coal devolatilization experiments are commonly conducted at moderate temperatures (800 to 1300 K) and heating rates (103 to 104 Ks−1) in inert environments in order to measure evolved species before secondary reaction in the gas phase. However, chars from these experiments exhibit different physical characteristics than chars obtained under typical combustion conditions (1500 to 2000 K, 105 Ks−1, and 3 to 10 mol% oxygen). Experiments were conducted in two laminar, entrained-flow reactors to determine characteristics of coal chars in inert and oxygen-rich environments. One flow reactor was heated electrically, with gas temperatures of …

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Overview Of Acerc Comprehensive Model Development, Thomas H. Fletcher, Scott C. Hill Jan 1993

Overview Of Acerc Comprehensive Model Development, Thomas H. Fletcher, Scott C. Hill

Faculty Publications

A major objective of the Advanced Combustion Engineering Research Center (ACERC) is the development of comprehensive combustion models to help in the solution of critical national combustion problems. Computer models incorporate research and technology results from center projects and from external research programs. The synergistic integration of scientific knowledge that is expected from the NSF engineering research centers is demonstrated to a great extent at ACERC by the development of these software tools. The transfer of technology from ACERC to industry is also accomplished in part by the implementation of the models at industrial firms. The effort to develop such …

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